“…A number of researches have been reported to focus on the synthetic methods and characterizations of rare earth fluoride and rare earth doped alkaline-earth fluoride using the HF [1], trifluoro-acetates [2][3][4][5] and 1,1,1-trifluoro-5-methyl-2,4-hexanedione [6]. Above all, the luminescent [7,8], scintillation properties [9,10] and applications to the solar cell [11] have been studied for Eu doped CaF 2 single crystal.…”